1. Technical Field
The present invention relates generally to a semiconductor apparatus and a semiconductor memory apparatus, and more particularly to a technology for efficiently transferring a control voltage.
2. Related Art
In a programming operation state of a flash memory apparatus having a plurality of local word lines, a certain local word line selected among the plurality of local word lines would be driven with a word line programming voltage, but the unselected local word lines are driven with a word line pass voltage which is at a lower voltage level than the word line programming voltage.
The word line programming voltage and the word line pass voltage that were generated by an internal voltage generation circuit are transmitted through global word lines, and these voltages are selectively transferred to the appropriate local word lines through voltage transfer transistors. The voltage transfer transistors are controlled through a select signal having a high voltage level so as to secure voltage transfer efficiency.
The word line programming voltage described above is considered a very high voltage in the flash memory applications. With rising word line programming voltage, the threshold voltage (Vth) of the voltage transfer transistors will also increase due to the body effect and others. However, the threshold voltage of the voltage in transfer transistors when elevated will deteriorate the voltage transfer efficiency. This problem of deteriorated voltage transfer efficiency due to the elevated level of threshold voltage of the voltage transfer transistors can be coped by raising the voltage level of the select signal for controlling the voltage transfer transistors. However, when considering the breakdown voltage of the transistors, there are limitations in raising the voltage level of the select signal in the internal voltage generation circuit.